An Istanbul court of appeal on Tuesday upheld aggravated life sentences of six suspects over links to the Fetullah Terrorist Organization (FETO), the group behind the 2016 defeated coup in Turkey, a judicial source said.

Nazli Ilicak, Ahmet Altan, Mehmet Altan, Fevzi Yazici, Yakup Simsek and Sukru Tugrul Ozsengul were convicted for attempting to overthrow the constitutional order, said the source, who asked not to be named due to restrictions on talking to the media.

They had appealed to the high court for their release, but Istanbul’s 2nd Appeal Court upheld their sentence, the source added. 

In late June, columnist and academic Mehmet Altan was released under judicial control upon his appeal to the penal department of Istanbul’s regional court of justice. 

FETO and its U.S.-based leader Fetullah Gulen orchestrated the defeated coup of July 15, 2016 that martyred 250 people and injured nearly 2,200 others. 

Ankara accuses FETO of being behind a long-running campaign to overthrow the state through the infiltration of Turkish institutions, particularly the military, police, and judiciary.